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X-Ray Spectral Morphologies of Young Supernova Remnants John P. Hughes Rutgers University. Parviz Ghavamian, Rutgers Pat Slane, CfA Sangwook Park, Penn State Gordon Garmire, Penn State Anne Decourchelle, Saclay. Cara Rakowski, Rutgers Jessica Warren, Rutgers - PowerPoint PPT Presentation
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October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 11
X-Ray Spectral X-Ray Spectral Morphologies of Young Morphologies of Young Supernova RemnantsSupernova Remnants
John P. HughesJohn P. HughesRutgers UniversityRutgers University
Cara Rakowski, Rutgers
Jessica Warren, Rutgers
Dave Burrows, Penn State
John Nousek, Penn State
Peter Roming, Penn State
Parviz Ghavamian, Rutgers
Pat Slane, CfA
Sangwook Park, Penn State
Gordon Garmire, Penn State
Anne Decourchelle, Saclay
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 22
Young Supernova RemnantsYoung Supernova Remnants
NucleosynthesisNucleosynthesis Explosion Mechanism: neutrino driven convection, jets ?Explosion Mechanism: neutrino driven convection, jets ? Progenitor mass, influence on environmentProgenitor mass, influence on environment Compact objects, pulsars and pulsar wind nebula (PWN)Compact objects, pulsars and pulsar wind nebula (PWN) Cosmic ray accelerationCosmic ray acceleration Dynamical evolution of SNRsDynamical evolution of SNRs Physics of high Mach number shocksPhysics of high Mach number shocks
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 33
Overturning Our View of Cas AOverturning Our View of Cas A
Hughes, Rakowski, Burrows, and Slane 2000, ApJL, 528, L109.
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 44
Oxygen-Rich SNR G292.0+1.8Oxygen-Rich SNR G292.0+1.8
Park et al 2001, ApJL, 564, L39
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 55
Oxygen-Rich SNR G292.0+1.8Oxygen-Rich SNR G292.0+1.8
Ejecta
Rich in O, Ne, and Mg, some Si
[O]/[Ne] < 1
No Si-rich or Fe-rich ejecta
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 66
Oxygen-Rich SNR G292.0+1.8Oxygen-Rich SNR G292.0+1.8
Normal Composition, CSM
Central bright bar – an axisymmetric stellar wind (Blondin et al, 1996)
Thin, circumferential filaments enclose ejecta-dominated material – red/blue supergiant winbd boundary
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 77
Oxygen-Rich SNR G292.0+1.8Oxygen-Rich SNR G292.0+1.8Point source
Featureless power-law spectrum, photon index = 1.7
Surrounded by diffuse X-ray/radio nebula
Off center, implied speed of ~800 km/s
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 88
PSR J1124-5916 in G292.0+1.8PSR J1124-5916 in G292.0+1.8 Discovered at Parkes (Camilo et al 2002)Discovered at Parkes (Camilo et al 2002) P=0.1353140749 s, dP/dt=7.471E-13P=0.1353140749 s, dP/dt=7.471E-13 Characteristic age ~ 2900 yrs (SNR age ~ 1600 yrs)Characteristic age ~ 2900 yrs (SNR age ~ 1600 yrs) Not detected in coherent FFT of Chandra HRC observationNot detected in coherent FFT of Chandra HRC observation 3.5 sigma detection from Z3.5 sigma detection from Znn
22 test at radio parameters test at radio parameters Only ~130 pulsed events in 50 ksOnly ~130 pulsed events in 50 ks
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 99
PSR J1124-5916PSR J1124-5916 Image Analysis: point source and elliptical gaussian (small Image Analysis: point source and elliptical gaussian (small
nebula)nebula) Point source contains ~160 X-ray eventsPoint source contains ~160 X-ray events Pulsed fraction high ~80%Pulsed fraction high ~80% Unpulsed point source emission < 1.4E-3 cts/sUnpulsed point source emission < 1.4E-3 cts/s LLBBBB< 10< 103333 erg/s erg/s
Below standard cooling curve for 2000 yr old PSRBelow standard cooling curve for 2000 yr old PSR
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 1010
DEM L71: Ejecta and Shock DEM L71: Ejecta and Shock PhysicsPhysics
H alphaSoft X-ray
Hughes, Ghavamian, Rakowski, and Slane, ApJL, in prep
Rutgers Fabry-Perot/NOAOChandra/NASA
Hard X-ray
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 1111
Fe-Rich EjectaFe-Rich Ejecta
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 1212
Properties of DEM L71 EjectaProperties of DEM L71 Ejecta Outer rim: lowered abundances, ~0.2 solar (LMC ISM)Outer rim: lowered abundances, ~0.2 solar (LMC ISM) Core: enhanced Fe abundance, [Fe]/[O] > 5 times solar (ejecta)Core: enhanced Fe abundance, [Fe]/[O] > 5 times solar (ejecta) Thick elliptical shell, 32” by 40” across (3.9 pc by 4.8 pc)Thick elliptical shell, 32” by 40” across (3.9 pc by 4.8 pc) Dynamical mass estimate Dynamical mass estimate
r’ ~ 3.0Mej = 1.1 Mch (n/0.5 cm-3)
Wang & Chevalier 2001
EM mass estimateEM mass estimate
EM ~ ne nFe VMFe < 2 Msun
Main error: source of Main error: source of electronselectrons
Fe-rich, low mass SN Ia
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 1313
DEM L71: Shock PhysicsDEM L71: Shock PhysicsNonradiative Balmer-dominated shockMeasure post-shock proton temperature
X-ray emission from thermal bremsstralungMeasure post-shock electron temperature
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 1414
Nonradiative Balmer ShocksNonradiative Balmer Shocks
Nonradiative means that a radiative Nonradiative means that a radiative (cooling) zone does not form(cooling) zone does not form
Low density (partially neutral) gasLow density (partially neutral) gas High velocity shocksHigh velocity shocks Narrow component: cold H I overrun Narrow component: cold H I overrun
by shock, collisionally excitedby shock, collisionally excited Broad component: hot postshock Broad component: hot postshock
protons that charge exchange with protons that charge exchange with cold H Icold H I
Ghavamian, Rakowski, Hughes, and Williams 2002, ApJ, in prep.
Width of broad component yields post shock proton temperature
(Chevalier & Raymond 1978; Chevalier, Kirshner, & Raymond 1980)
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 1515
Constraining the Electron Constraining the Electron TemperatureTemperature
Fit NEI shock models to 3 spatial Fit NEI shock models to 3 spatial zones to follow evolution of Tzones to follow evolution of Tee
Study 5 azimuthal regions with Study 5 azimuthal regions with sufficient Chandra statistics and sufficient Chandra statistics and broad Halpha componentbroad Halpha component
Available data cannot constrain Available data cannot constrain TTe e gradientsgradients
Rakowski, Ghavamian, Hughes, & Williams 2002, ApJ, in prep.
Data do determine mean Te
Suggest partial to compete temperature equilibration
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 1616
Results on TResults on Tee/T/Tp p from DEM L71from DEM L71
Shows trend for higher equilibration for lower speed shocksShows trend for higher equilibration for lower speed shocks X-ray/Halpha results consistent with other purely Halpha onesX-ray/Halpha results consistent with other purely Halpha ones
October 10, 2002October 10, 2002 COSPAR Houston, TXCOSPAR Houston, TX 1717
THE ENDTHE END